Powder coating systems apply powder paints and coatings to a variety of products and parts. Such systems, particularly including electrostatic powder coating systems, can become quite complex, often including a plurality of spray guns with a plurality of electrical characteristics, or parameters. Control of the spray guns and other components and parameters is a critical component of the powder coating system.
It is known in the art to decentralize control of certain electrical characteristics of each spray gun by using a spray gun controller to control each spray gun in a system. In such a decentralized system, each spray gun controller includes a processor, memory and parameters stored in such memory to control a single gun. Such a system is shown in U.S. Pat. Nos. 5,718,767, 5,843,515, 6,017,394 and 6,132,511 (the “'767 et. seq. Patents”) owned in common by the assignee of the present invention, the entire disclosures of which are fully incorporated herein by reference. Even under such decentralized systems, however, there is a need to centrally control all of the gun controllers and other components of the system, such as air pumps, booth functions, etc. In the systems shown in the '767 et. seq. Patents, centralized control is attempted by use of multiple processors on multiple printed circuit boards, which each processor controlling a different set of components. For example, a system of the '767 et. seq. Patents uses five processors to control the gun controllers, part position control, operator control, external pc control and gateway central processing.
Various systems have been developed which reduce the number of processors involved in centralized control of a powder coating system. Such a system is shown in the '465 Patent, and in powder coating control systems commercially available from the assignee of the present invention under the trademarks SURE COAT®, VERSA-SCREEN® and SMART-COAT® (the above-referenced systems collectively the “Sure/Smart Coat Systems”). In such systems, at least two processors are used to control just the gun controllers—one processor for the component of the system which communicates with the gun controllers and one processor for an operator control panel which centralizes some system control features. If automatic (i.e., remote) control is desired, or if control of other system components, such as booth controls or digital air flow controllers is desired, at least a third processor in a connected programmable logic controller (a “PLC”) is required.
The required use of multiple processors for centralized control of a powder coating system increases the complexity and cost of such a system. Therefore, it is highly desirable to provide a central control for a powder coating system which uses a reduced number of processors to control the gun controllers and other components of the system. Furthermore, the use of multiple processors generally requires multiple operator interfaces to view and control all system parameters. Therefore, it is also highly desirable to provide a central control for a powder coating system which uses a reduced number of processors and a single operator interface to view and control all of the system parameters.
The required use of multiple processors furthermore typically requires multiple enclosures to house multiple components of a controller of a powder coating system, further increasing the cost and complexity of the system. It is thus highly desirable to provide a controller for a powder coating system which is contained in a single enclosure.